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Miklos Szeredi334f4852005-09-09 13:10:27 -07001/*
2 FUSE: Filesystem in Userspace
Miklos Szeredi1729a162008-11-26 12:03:54 +01003 Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu>
Miklos Szeredi334f4852005-09-09 13:10:27 -07004
5 This program can be distributed under the terms of the GNU GPL.
6 See the file COPYING.
7*/
8
9#include "fuse_i.h"
10
11#include <linux/init.h>
12#include <linux/module.h>
13#include <linux/poll.h>
14#include <linux/uio.h>
15#include <linux/miscdevice.h>
16#include <linux/pagemap.h>
17#include <linux/file.h>
18#include <linux/slab.h>
Miklos Szeredidd3bb142010-05-25 15:06:06 +020019#include <linux/pipe_fs_i.h>
Miklos Szeredice534fb2010-05-25 15:06:07 +020020#include <linux/swap.h>
21#include <linux/splice.h>
Miklos Szeredi334f4852005-09-09 13:10:27 -070022
23MODULE_ALIAS_MISCDEV(FUSE_MINOR);
Kay Sievers578454f2010-05-20 18:07:20 +020024MODULE_ALIAS("devname:fuse");
Miklos Szeredi334f4852005-09-09 13:10:27 -070025
Christoph Lametere18b8902006-12-06 20:33:20 -080026static struct kmem_cache *fuse_req_cachep;
Miklos Szeredi334f4852005-09-09 13:10:27 -070027
Miklos Szeredi8bfc0162006-01-16 22:14:28 -080028static struct fuse_conn *fuse_get_conn(struct file *file)
Miklos Szeredi334f4852005-09-09 13:10:27 -070029{
Miklos Szeredi0720b312006-04-10 22:54:55 -070030 /*
31 * Lockless access is OK, because file->private data is set
32 * once during mount and is valid until the file is released.
33 */
34 return file->private_data;
Miklos Szeredi334f4852005-09-09 13:10:27 -070035}
36
Miklos Szeredi8bfc0162006-01-16 22:14:28 -080037static void fuse_request_init(struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -070038{
39 memset(req, 0, sizeof(*req));
40 INIT_LIST_HEAD(&req->list);
Miklos Szeredia4d27e72006-06-25 05:48:54 -070041 INIT_LIST_HEAD(&req->intr_entry);
Miklos Szeredi334f4852005-09-09 13:10:27 -070042 init_waitqueue_head(&req->waitq);
43 atomic_set(&req->count, 1);
44}
45
46struct fuse_req *fuse_request_alloc(void)
47{
Christoph Lametere94b1762006-12-06 20:33:17 -080048 struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, GFP_KERNEL);
Miklos Szeredi334f4852005-09-09 13:10:27 -070049 if (req)
50 fuse_request_init(req);
51 return req;
52}
Tejun Heo08cbf542009-04-14 10:54:53 +090053EXPORT_SYMBOL_GPL(fuse_request_alloc);
Miklos Szeredi334f4852005-09-09 13:10:27 -070054
Miklos Szeredi3be5a522008-04-30 00:54:41 -070055struct fuse_req *fuse_request_alloc_nofs(void)
56{
57 struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, GFP_NOFS);
58 if (req)
59 fuse_request_init(req);
60 return req;
61}
62
Miklos Szeredi334f4852005-09-09 13:10:27 -070063void fuse_request_free(struct fuse_req *req)
64{
65 kmem_cache_free(fuse_req_cachep, req);
66}
67
Miklos Szeredi8bfc0162006-01-16 22:14:28 -080068static void block_sigs(sigset_t *oldset)
Miklos Szeredi334f4852005-09-09 13:10:27 -070069{
70 sigset_t mask;
71
72 siginitsetinv(&mask, sigmask(SIGKILL));
73 sigprocmask(SIG_BLOCK, &mask, oldset);
74}
75
Miklos Szeredi8bfc0162006-01-16 22:14:28 -080076static void restore_sigs(sigset_t *oldset)
Miklos Szeredi334f4852005-09-09 13:10:27 -070077{
78 sigprocmask(SIG_SETMASK, oldset, NULL);
79}
80
Miklos Szeredi334f4852005-09-09 13:10:27 -070081static void __fuse_get_request(struct fuse_req *req)
82{
83 atomic_inc(&req->count);
84}
85
86/* Must be called with > 1 refcount */
87static void __fuse_put_request(struct fuse_req *req)
88{
89 BUG_ON(atomic_read(&req->count) < 2);
90 atomic_dec(&req->count);
91}
92
Miklos Szeredi33649c92006-06-25 05:48:52 -070093static void fuse_req_init_context(struct fuse_req *req)
94{
David Howells2186a712008-11-14 10:38:53 +110095 req->in.h.uid = current_fsuid();
96 req->in.h.gid = current_fsgid();
Miklos Szeredi33649c92006-06-25 05:48:52 -070097 req->in.h.pid = current->pid;
98}
99
Miklos Szeredice1d5a42006-04-10 22:54:58 -0700100struct fuse_req *fuse_get_req(struct fuse_conn *fc)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700101{
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700102 struct fuse_req *req;
103 sigset_t oldset;
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200104 int intr;
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700105 int err;
106
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200107 atomic_inc(&fc->num_waiting);
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700108 block_sigs(&oldset);
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200109 intr = wait_event_interruptible(fc->blocked_waitq, !fc->blocked);
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700110 restore_sigs(&oldset);
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200111 err = -EINTR;
112 if (intr)
113 goto out;
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700114
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700115 err = -ENOTCONN;
116 if (!fc->connected)
117 goto out;
118
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700119 req = fuse_request_alloc();
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200120 err = -ENOMEM;
Miklos Szeredice1d5a42006-04-10 22:54:58 -0700121 if (!req)
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200122 goto out;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700123
Miklos Szeredi33649c92006-06-25 05:48:52 -0700124 fuse_req_init_context(req);
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200125 req->waiting = 1;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700126 return req;
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200127
128 out:
129 atomic_dec(&fc->num_waiting);
130 return ERR_PTR(err);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700131}
Tejun Heo08cbf542009-04-14 10:54:53 +0900132EXPORT_SYMBOL_GPL(fuse_get_req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700133
Miklos Szeredi33649c92006-06-25 05:48:52 -0700134/*
135 * Return request in fuse_file->reserved_req. However that may
136 * currently be in use. If that is the case, wait for it to become
137 * available.
138 */
139static struct fuse_req *get_reserved_req(struct fuse_conn *fc,
140 struct file *file)
141{
142 struct fuse_req *req = NULL;
143 struct fuse_file *ff = file->private_data;
144
145 do {
Miklos Szeredide5e3de2007-10-16 23:31:00 -0700146 wait_event(fc->reserved_req_waitq, ff->reserved_req);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700147 spin_lock(&fc->lock);
148 if (ff->reserved_req) {
149 req = ff->reserved_req;
150 ff->reserved_req = NULL;
151 get_file(file);
152 req->stolen_file = file;
153 }
154 spin_unlock(&fc->lock);
155 } while (!req);
156
157 return req;
158}
159
160/*
161 * Put stolen request back into fuse_file->reserved_req
162 */
163static void put_reserved_req(struct fuse_conn *fc, struct fuse_req *req)
164{
165 struct file *file = req->stolen_file;
166 struct fuse_file *ff = file->private_data;
167
168 spin_lock(&fc->lock);
169 fuse_request_init(req);
170 BUG_ON(ff->reserved_req);
171 ff->reserved_req = req;
Miklos Szeredide5e3de2007-10-16 23:31:00 -0700172 wake_up_all(&fc->reserved_req_waitq);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700173 spin_unlock(&fc->lock);
174 fput(file);
175}
176
177/*
178 * Gets a requests for a file operation, always succeeds
179 *
180 * This is used for sending the FLUSH request, which must get to
181 * userspace, due to POSIX locks which may need to be unlocked.
182 *
183 * If allocation fails due to OOM, use the reserved request in
184 * fuse_file.
185 *
186 * This is very unlikely to deadlock accidentally, since the
187 * filesystem should not have it's own file open. If deadlock is
188 * intentional, it can still be broken by "aborting" the filesystem.
189 */
190struct fuse_req *fuse_get_req_nofail(struct fuse_conn *fc, struct file *file)
191{
192 struct fuse_req *req;
193
194 atomic_inc(&fc->num_waiting);
195 wait_event(fc->blocked_waitq, !fc->blocked);
196 req = fuse_request_alloc();
197 if (!req)
198 req = get_reserved_req(fc, file);
199
200 fuse_req_init_context(req);
201 req->waiting = 1;
202 return req;
203}
204
Miklos Szeredi334f4852005-09-09 13:10:27 -0700205void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req)
206{
Miklos Szeredi7128ec22006-02-04 23:27:40 -0800207 if (atomic_dec_and_test(&req->count)) {
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200208 if (req->waiting)
209 atomic_dec(&fc->num_waiting);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700210
211 if (req->stolen_file)
212 put_reserved_req(fc, req);
213 else
214 fuse_request_free(req);
Miklos Szeredi7128ec22006-02-04 23:27:40 -0800215 }
216}
Tejun Heo08cbf542009-04-14 10:54:53 +0900217EXPORT_SYMBOL_GPL(fuse_put_request);
Miklos Szeredi7128ec22006-02-04 23:27:40 -0800218
Miklos Szeredid12def12008-02-06 01:38:39 -0800219static unsigned len_args(unsigned numargs, struct fuse_arg *args)
220{
221 unsigned nbytes = 0;
222 unsigned i;
223
224 for (i = 0; i < numargs; i++)
225 nbytes += args[i].size;
226
227 return nbytes;
228}
229
230static u64 fuse_get_unique(struct fuse_conn *fc)
231{
232 fc->reqctr++;
233 /* zero is special */
234 if (fc->reqctr == 0)
235 fc->reqctr = 1;
236
237 return fc->reqctr;
238}
239
240static void queue_request(struct fuse_conn *fc, struct fuse_req *req)
241{
242 req->in.h.unique = fuse_get_unique(fc);
243 req->in.h.len = sizeof(struct fuse_in_header) +
244 len_args(req->in.numargs, (struct fuse_arg *) req->in.args);
245 list_add_tail(&req->list, &fc->pending);
246 req->state = FUSE_REQ_PENDING;
247 if (!req->waiting) {
248 req->waiting = 1;
249 atomic_inc(&fc->num_waiting);
250 }
251 wake_up(&fc->waitq);
252 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
253}
254
255static void flush_bg_queue(struct fuse_conn *fc)
256{
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700257 while (fc->active_background < fc->max_background &&
Miklos Szeredid12def12008-02-06 01:38:39 -0800258 !list_empty(&fc->bg_queue)) {
259 struct fuse_req *req;
260
261 req = list_entry(fc->bg_queue.next, struct fuse_req, list);
262 list_del(&req->list);
263 fc->active_background++;
264 queue_request(fc, req);
265 }
266}
267
Miklos Szeredi6dbbcb12006-04-26 10:49:06 +0200268/*
Miklos Szeredi334f4852005-09-09 13:10:27 -0700269 * This function is called when a request is finished. Either a reply
Miklos Szeredif9a28422006-06-25 05:48:53 -0700270 * has arrived or it was aborted (and not yet sent) or some error
Miklos Szeredif43b1552006-01-16 22:14:26 -0800271 * occurred during communication with userspace, or the device file
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700272 * was closed. The requester thread is woken up (if still waiting),
273 * the 'end' callback is called if given, else the reference to the
274 * request is released
Miklos Szeredi7128ec22006-02-04 23:27:40 -0800275 *
Miklos Szeredid7133112006-04-10 22:54:55 -0700276 * Called with fc->lock, unlocks it
Miklos Szeredi334f4852005-09-09 13:10:27 -0700277 */
278static void request_end(struct fuse_conn *fc, struct fuse_req *req)
Harvey Harrison5d9ec852008-12-02 14:49:42 +0100279__releases(&fc->lock)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700280{
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700281 void (*end) (struct fuse_conn *, struct fuse_req *) = req->end;
282 req->end = NULL;
Miklos Szeredid77a1d52006-01-16 22:14:31 -0800283 list_del(&req->list);
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700284 list_del(&req->intr_entry);
Miklos Szeredi83cfd492006-01-16 22:14:31 -0800285 req->state = FUSE_REQ_FINISHED;
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700286 if (req->background) {
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700287 if (fc->num_background == fc->max_background) {
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700288 fc->blocked = 0;
289 wake_up_all(&fc->blocked_waitq);
290 }
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700291 if (fc->num_background == fc->congestion_threshold &&
Tejun Heoa325f9b2009-04-14 10:54:52 +0900292 fc->connected && fc->bdi_initialized) {
Jens Axboe8aa7e842009-07-09 14:52:32 +0200293 clear_bdi_congested(&fc->bdi, BLK_RW_SYNC);
294 clear_bdi_congested(&fc->bdi, BLK_RW_ASYNC);
Miklos Szeredif92b99b2007-10-16 23:30:59 -0700295 }
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700296 fc->num_background--;
Miklos Szeredid12def12008-02-06 01:38:39 -0800297 fc->active_background--;
298 flush_bg_queue(fc);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700299 }
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700300 spin_unlock(&fc->lock);
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700301 wake_up(&req->waitq);
302 if (end)
303 end(fc, req);
Tejun Heoe9bb09d2008-11-26 12:03:54 +0100304 fuse_put_request(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700305}
306
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700307static void wait_answer_interruptible(struct fuse_conn *fc,
308 struct fuse_req *req)
Harvey Harrison5d9ec852008-12-02 14:49:42 +0100309__releases(&fc->lock)
310__acquires(&fc->lock)
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700311{
312 if (signal_pending(current))
313 return;
314
315 spin_unlock(&fc->lock);
316 wait_event_interruptible(req->waitq, req->state == FUSE_REQ_FINISHED);
317 spin_lock(&fc->lock);
318}
319
320static void queue_interrupt(struct fuse_conn *fc, struct fuse_req *req)
321{
322 list_add_tail(&req->intr_entry, &fc->interrupts);
323 wake_up(&fc->waitq);
324 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
325}
326
Miklos Szeredi7c352bd2005-09-09 13:10:39 -0700327static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
Harvey Harrison5d9ec852008-12-02 14:49:42 +0100328__releases(&fc->lock)
329__acquires(&fc->lock)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700330{
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700331 if (!fc->no_interrupt) {
332 /* Any signal may interrupt this */
333 wait_answer_interruptible(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700334
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700335 if (req->aborted)
336 goto aborted;
337 if (req->state == FUSE_REQ_FINISHED)
338 return;
339
340 req->interrupted = 1;
341 if (req->state == FUSE_REQ_SENT)
342 queue_interrupt(fc, req);
343 }
344
Miklos Szeredia131de02007-10-16 23:31:04 -0700345 if (!req->force) {
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700346 sigset_t oldset;
347
348 /* Only fatal signals may interrupt this */
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700349 block_sigs(&oldset);
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700350 wait_answer_interruptible(fc, req);
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700351 restore_sigs(&oldset);
Miklos Szeredia131de02007-10-16 23:31:04 -0700352
353 if (req->aborted)
354 goto aborted;
355 if (req->state == FUSE_REQ_FINISHED)
356 return;
357
358 /* Request is not yet in userspace, bail out */
359 if (req->state == FUSE_REQ_PENDING) {
360 list_del(&req->list);
361 __fuse_put_request(req);
362 req->out.h.error = -EINTR;
363 return;
364 }
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700365 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700366
Miklos Szeredia131de02007-10-16 23:31:04 -0700367 /*
368 * Either request is already in userspace, or it was forced.
369 * Wait it out.
370 */
371 spin_unlock(&fc->lock);
372 wait_event(req->waitq, req->state == FUSE_REQ_FINISHED);
373 spin_lock(&fc->lock);
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700374
Miklos Szeredia131de02007-10-16 23:31:04 -0700375 if (!req->aborted)
376 return;
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700377
378 aborted:
Miklos Szeredia131de02007-10-16 23:31:04 -0700379 BUG_ON(req->state != FUSE_REQ_FINISHED);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700380 if (req->locked) {
381 /* This is uninterruptible sleep, because data is
382 being copied to/from the buffers of req. During
383 locked state, there mustn't be any filesystem
384 operation (e.g. page fault), since that could lead
385 to deadlock */
Miklos Szeredid7133112006-04-10 22:54:55 -0700386 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700387 wait_event(req->waitq, !req->locked);
Miklos Szeredid7133112006-04-10 22:54:55 -0700388 spin_lock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700389 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700390}
391
Tejun Heob93f8582008-11-26 12:03:55 +0100392void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700393{
394 req->isreply = 1;
Miklos Szeredid7133112006-04-10 22:54:55 -0700395 spin_lock(&fc->lock);
Miklos Szeredi1e9a4ed2005-09-09 13:10:31 -0700396 if (!fc->connected)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700397 req->out.h.error = -ENOTCONN;
398 else if (fc->conn_error)
399 req->out.h.error = -ECONNREFUSED;
400 else {
401 queue_request(fc, req);
402 /* acquire extra reference, since request is still needed
403 after request_end() */
404 __fuse_get_request(req);
405
Miklos Szeredi7c352bd2005-09-09 13:10:39 -0700406 request_wait_answer(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700407 }
Miklos Szeredid7133112006-04-10 22:54:55 -0700408 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700409}
Tejun Heo08cbf542009-04-14 10:54:53 +0900410EXPORT_SYMBOL_GPL(fuse_request_send);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700411
Tejun Heob93f8582008-11-26 12:03:55 +0100412static void fuse_request_send_nowait_locked(struct fuse_conn *fc,
413 struct fuse_req *req)
Miklos Szeredid12def12008-02-06 01:38:39 -0800414{
415 req->background = 1;
416 fc->num_background++;
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700417 if (fc->num_background == fc->max_background)
Miklos Szeredid12def12008-02-06 01:38:39 -0800418 fc->blocked = 1;
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700419 if (fc->num_background == fc->congestion_threshold &&
Tejun Heoa325f9b2009-04-14 10:54:52 +0900420 fc->bdi_initialized) {
Jens Axboe8aa7e842009-07-09 14:52:32 +0200421 set_bdi_congested(&fc->bdi, BLK_RW_SYNC);
422 set_bdi_congested(&fc->bdi, BLK_RW_ASYNC);
Miklos Szeredid12def12008-02-06 01:38:39 -0800423 }
424 list_add_tail(&req->list, &fc->bg_queue);
425 flush_bg_queue(fc);
426}
427
Tejun Heob93f8582008-11-26 12:03:55 +0100428static void fuse_request_send_nowait(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700429{
Miklos Szeredid7133112006-04-10 22:54:55 -0700430 spin_lock(&fc->lock);
Miklos Szeredi1e9a4ed2005-09-09 13:10:31 -0700431 if (fc->connected) {
Tejun Heob93f8582008-11-26 12:03:55 +0100432 fuse_request_send_nowait_locked(fc, req);
Miklos Szeredid7133112006-04-10 22:54:55 -0700433 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700434 } else {
435 req->out.h.error = -ENOTCONN;
436 request_end(fc, req);
437 }
438}
439
Tejun Heob93f8582008-11-26 12:03:55 +0100440void fuse_request_send_noreply(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700441{
442 req->isreply = 0;
Tejun Heob93f8582008-11-26 12:03:55 +0100443 fuse_request_send_nowait(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700444}
445
Tejun Heob93f8582008-11-26 12:03:55 +0100446void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700447{
448 req->isreply = 1;
Tejun Heob93f8582008-11-26 12:03:55 +0100449 fuse_request_send_nowait(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700450}
Tejun Heo08cbf542009-04-14 10:54:53 +0900451EXPORT_SYMBOL_GPL(fuse_request_send_background);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700452
Miklos Szeredi334f4852005-09-09 13:10:27 -0700453/*
Miklos Szeredi3be5a522008-04-30 00:54:41 -0700454 * Called under fc->lock
455 *
456 * fc->connected must have been checked previously
457 */
Tejun Heob93f8582008-11-26 12:03:55 +0100458void fuse_request_send_background_locked(struct fuse_conn *fc,
459 struct fuse_req *req)
Miklos Szeredi3be5a522008-04-30 00:54:41 -0700460{
461 req->isreply = 1;
Tejun Heob93f8582008-11-26 12:03:55 +0100462 fuse_request_send_nowait_locked(fc, req);
Miklos Szeredi3be5a522008-04-30 00:54:41 -0700463}
464
465/*
Miklos Szeredi334f4852005-09-09 13:10:27 -0700466 * Lock the request. Up to the next unlock_request() there mustn't be
467 * anything that could cause a page-fault. If the request was already
Miklos Szeredif9a28422006-06-25 05:48:53 -0700468 * aborted bail out.
Miklos Szeredi334f4852005-09-09 13:10:27 -0700469 */
Miklos Szeredid7133112006-04-10 22:54:55 -0700470static int lock_request(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700471{
472 int err = 0;
473 if (req) {
Miklos Szeredid7133112006-04-10 22:54:55 -0700474 spin_lock(&fc->lock);
Miklos Szeredif9a28422006-06-25 05:48:53 -0700475 if (req->aborted)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700476 err = -ENOENT;
477 else
478 req->locked = 1;
Miklos Szeredid7133112006-04-10 22:54:55 -0700479 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700480 }
481 return err;
482}
483
484/*
Miklos Szeredif9a28422006-06-25 05:48:53 -0700485 * Unlock request. If it was aborted during being locked, the
Miklos Szeredi334f4852005-09-09 13:10:27 -0700486 * requester thread is currently waiting for it to be unlocked, so
487 * wake it up.
488 */
Miklos Szeredid7133112006-04-10 22:54:55 -0700489static void unlock_request(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700490{
491 if (req) {
Miklos Szeredid7133112006-04-10 22:54:55 -0700492 spin_lock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700493 req->locked = 0;
Miklos Szeredif9a28422006-06-25 05:48:53 -0700494 if (req->aborted)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700495 wake_up(&req->waitq);
Miklos Szeredid7133112006-04-10 22:54:55 -0700496 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700497 }
498}
499
500struct fuse_copy_state {
Miklos Szeredid7133112006-04-10 22:54:55 -0700501 struct fuse_conn *fc;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700502 int write;
503 struct fuse_req *req;
504 const struct iovec *iov;
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200505 struct pipe_buffer *pipebufs;
506 struct pipe_buffer *currbuf;
507 struct pipe_inode_info *pipe;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700508 unsigned long nr_segs;
509 unsigned long seglen;
510 unsigned long addr;
511 struct page *pg;
512 void *mapaddr;
513 void *buf;
514 unsigned len;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200515 unsigned move_pages:1;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700516};
517
Miklos Szeredid7133112006-04-10 22:54:55 -0700518static void fuse_copy_init(struct fuse_copy_state *cs, struct fuse_conn *fc,
Miklos Szeredic3021622010-05-25 15:06:07 +0200519 int write,
Miklos Szeredid7133112006-04-10 22:54:55 -0700520 const struct iovec *iov, unsigned long nr_segs)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700521{
522 memset(cs, 0, sizeof(*cs));
Miklos Szeredid7133112006-04-10 22:54:55 -0700523 cs->fc = fc;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700524 cs->write = write;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700525 cs->iov = iov;
526 cs->nr_segs = nr_segs;
527}
528
529/* Unmap and put previous page of userspace buffer */
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800530static void fuse_copy_finish(struct fuse_copy_state *cs)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700531{
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200532 if (cs->currbuf) {
533 struct pipe_buffer *buf = cs->currbuf;
534
Miklos Szeredic3021622010-05-25 15:06:07 +0200535 if (!cs->write) {
536 buf->ops->unmap(cs->pipe, buf, cs->mapaddr);
537 } else {
Miklos Szeredi7909b1c2010-07-12 14:41:40 +0200538 kunmap(buf->page);
Miklos Szeredic3021622010-05-25 15:06:07 +0200539 buf->len = PAGE_SIZE - cs->len;
540 }
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200541 cs->currbuf = NULL;
542 cs->mapaddr = NULL;
543 } else if (cs->mapaddr) {
Miklos Szeredi7909b1c2010-07-12 14:41:40 +0200544 kunmap(cs->pg);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700545 if (cs->write) {
546 flush_dcache_page(cs->pg);
547 set_page_dirty_lock(cs->pg);
548 }
549 put_page(cs->pg);
550 cs->mapaddr = NULL;
551 }
552}
553
554/*
555 * Get another pagefull of userspace buffer, and map it to kernel
556 * address space, and lock request
557 */
558static int fuse_copy_fill(struct fuse_copy_state *cs)
559{
560 unsigned long offset;
561 int err;
562
Miklos Szeredid7133112006-04-10 22:54:55 -0700563 unlock_request(cs->fc, cs->req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700564 fuse_copy_finish(cs);
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200565 if (cs->pipebufs) {
566 struct pipe_buffer *buf = cs->pipebufs;
567
Miklos Szeredic3021622010-05-25 15:06:07 +0200568 if (!cs->write) {
569 err = buf->ops->confirm(cs->pipe, buf);
570 if (err)
571 return err;
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200572
Miklos Szeredic3021622010-05-25 15:06:07 +0200573 BUG_ON(!cs->nr_segs);
574 cs->currbuf = buf;
Miklos Szeredi7909b1c2010-07-12 14:41:40 +0200575 cs->mapaddr = buf->ops->map(cs->pipe, buf, 0);
Miklos Szeredic3021622010-05-25 15:06:07 +0200576 cs->len = buf->len;
577 cs->buf = cs->mapaddr + buf->offset;
578 cs->pipebufs++;
579 cs->nr_segs--;
580 } else {
581 struct page *page;
582
583 if (cs->nr_segs == cs->pipe->buffers)
584 return -EIO;
585
586 page = alloc_page(GFP_HIGHUSER);
587 if (!page)
588 return -ENOMEM;
589
590 buf->page = page;
591 buf->offset = 0;
592 buf->len = 0;
593
594 cs->currbuf = buf;
Miklos Szeredi7909b1c2010-07-12 14:41:40 +0200595 cs->mapaddr = kmap(page);
Miklos Szeredic3021622010-05-25 15:06:07 +0200596 cs->buf = cs->mapaddr;
597 cs->len = PAGE_SIZE;
598 cs->pipebufs++;
599 cs->nr_segs++;
600 }
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200601 } else {
602 if (!cs->seglen) {
603 BUG_ON(!cs->nr_segs);
604 cs->seglen = cs->iov[0].iov_len;
605 cs->addr = (unsigned long) cs->iov[0].iov_base;
606 cs->iov++;
607 cs->nr_segs--;
608 }
609 err = get_user_pages_fast(cs->addr, 1, cs->write, &cs->pg);
610 if (err < 0)
611 return err;
612 BUG_ON(err != 1);
613 offset = cs->addr % PAGE_SIZE;
Miklos Szeredi7909b1c2010-07-12 14:41:40 +0200614 cs->mapaddr = kmap(cs->pg);
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200615 cs->buf = cs->mapaddr + offset;
616 cs->len = min(PAGE_SIZE - offset, cs->seglen);
617 cs->seglen -= cs->len;
618 cs->addr += cs->len;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700619 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700620
Miklos Szeredid7133112006-04-10 22:54:55 -0700621 return lock_request(cs->fc, cs->req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700622}
623
624/* Do as much copy to/from userspace buffer as we can */
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800625static int fuse_copy_do(struct fuse_copy_state *cs, void **val, unsigned *size)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700626{
627 unsigned ncpy = min(*size, cs->len);
628 if (val) {
629 if (cs->write)
630 memcpy(cs->buf, *val, ncpy);
631 else
632 memcpy(*val, cs->buf, ncpy);
633 *val += ncpy;
634 }
635 *size -= ncpy;
636 cs->len -= ncpy;
637 cs->buf += ncpy;
638 return ncpy;
639}
640
Miklos Szeredice534fb2010-05-25 15:06:07 +0200641static int fuse_check_page(struct page *page)
642{
643 if (page_mapcount(page) ||
644 page->mapping != NULL ||
645 page_count(page) != 1 ||
646 (page->flags & PAGE_FLAGS_CHECK_AT_PREP &
647 ~(1 << PG_locked |
648 1 << PG_referenced |
649 1 << PG_uptodate |
650 1 << PG_lru |
651 1 << PG_active |
652 1 << PG_reclaim))) {
653 printk(KERN_WARNING "fuse: trying to steal weird page\n");
654 printk(KERN_WARNING " page=%p index=%li flags=%08lx, count=%i, mapcount=%i, mapping=%p\n", page, page->index, page->flags, page_count(page), page_mapcount(page), page->mapping);
655 return 1;
656 }
657 return 0;
658}
659
660static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
661{
662 int err;
663 struct page *oldpage = *pagep;
664 struct page *newpage;
665 struct pipe_buffer *buf = cs->pipebufs;
666 struct address_space *mapping;
667 pgoff_t index;
668
669 unlock_request(cs->fc, cs->req);
670 fuse_copy_finish(cs);
671
672 err = buf->ops->confirm(cs->pipe, buf);
673 if (err)
674 return err;
675
676 BUG_ON(!cs->nr_segs);
677 cs->currbuf = buf;
678 cs->len = buf->len;
679 cs->pipebufs++;
680 cs->nr_segs--;
681
682 if (cs->len != PAGE_SIZE)
683 goto out_fallback;
684
685 if (buf->ops->steal(cs->pipe, buf) != 0)
686 goto out_fallback;
687
688 newpage = buf->page;
689
690 if (WARN_ON(!PageUptodate(newpage)))
691 return -EIO;
692
693 ClearPageMappedToDisk(newpage);
694
695 if (fuse_check_page(newpage) != 0)
696 goto out_fallback_unlock;
697
698 mapping = oldpage->mapping;
699 index = oldpage->index;
700
701 /*
702 * This is a new and locked page, it shouldn't be mapped or
703 * have any special flags on it
704 */
705 if (WARN_ON(page_mapped(oldpage)))
706 goto out_fallback_unlock;
707 if (WARN_ON(page_has_private(oldpage)))
708 goto out_fallback_unlock;
709 if (WARN_ON(PageDirty(oldpage) || PageWriteback(oldpage)))
710 goto out_fallback_unlock;
711 if (WARN_ON(PageMlocked(oldpage)))
712 goto out_fallback_unlock;
713
714 remove_from_page_cache(oldpage);
715 page_cache_release(oldpage);
716
717 err = add_to_page_cache_locked(newpage, mapping, index, GFP_KERNEL);
718 if (err) {
719 printk(KERN_WARNING "fuse_try_move_page: failed to add page");
720 goto out_fallback_unlock;
721 }
722 page_cache_get(newpage);
723
724 if (!(buf->flags & PIPE_BUF_FLAG_LRU))
725 lru_cache_add_file(newpage);
726
727 err = 0;
728 spin_lock(&cs->fc->lock);
729 if (cs->req->aborted)
730 err = -ENOENT;
731 else
732 *pagep = newpage;
733 spin_unlock(&cs->fc->lock);
734
735 if (err) {
736 unlock_page(newpage);
737 page_cache_release(newpage);
738 return err;
739 }
740
741 unlock_page(oldpage);
742 page_cache_release(oldpage);
743 cs->len = 0;
744
745 return 0;
746
747out_fallback_unlock:
748 unlock_page(newpage);
749out_fallback:
750 cs->mapaddr = buf->ops->map(cs->pipe, buf, 1);
751 cs->buf = cs->mapaddr + buf->offset;
752
753 err = lock_request(cs->fc, cs->req);
754 if (err)
755 return err;
756
757 return 1;
758}
759
Miklos Szeredic3021622010-05-25 15:06:07 +0200760static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page,
761 unsigned offset, unsigned count)
762{
763 struct pipe_buffer *buf;
764
765 if (cs->nr_segs == cs->pipe->buffers)
766 return -EIO;
767
768 unlock_request(cs->fc, cs->req);
769 fuse_copy_finish(cs);
770
771 buf = cs->pipebufs;
772 page_cache_get(page);
773 buf->page = page;
774 buf->offset = offset;
775 buf->len = count;
776
777 cs->pipebufs++;
778 cs->nr_segs++;
779 cs->len = 0;
780
781 return 0;
782}
783
Miklos Szeredi334f4852005-09-09 13:10:27 -0700784/*
785 * Copy a page in the request to/from the userspace buffer. Must be
786 * done atomically
787 */
Miklos Szeredice534fb2010-05-25 15:06:07 +0200788static int fuse_copy_page(struct fuse_copy_state *cs, struct page **pagep,
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800789 unsigned offset, unsigned count, int zeroing)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700790{
Miklos Szeredice534fb2010-05-25 15:06:07 +0200791 int err;
792 struct page *page = *pagep;
793
Miklos Szeredi334f4852005-09-09 13:10:27 -0700794 if (page && zeroing && count < PAGE_SIZE) {
795 void *mapaddr = kmap_atomic(page, KM_USER1);
796 memset(mapaddr, 0, PAGE_SIZE);
797 kunmap_atomic(mapaddr, KM_USER1);
798 }
799 while (count) {
Miklos Szeredic3021622010-05-25 15:06:07 +0200800 if (cs->write && cs->pipebufs && page) {
801 return fuse_ref_page(cs, page, offset, count);
802 } else if (!cs->len) {
Miklos Szeredice534fb2010-05-25 15:06:07 +0200803 if (cs->move_pages && page &&
804 offset == 0 && count == PAGE_SIZE) {
805 err = fuse_try_move_page(cs, pagep);
806 if (err <= 0)
807 return err;
808 } else {
809 err = fuse_copy_fill(cs);
810 if (err)
811 return err;
812 }
Miklos Szeredi1729a162008-11-26 12:03:54 +0100813 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700814 if (page) {
815 void *mapaddr = kmap_atomic(page, KM_USER1);
816 void *buf = mapaddr + offset;
817 offset += fuse_copy_do(cs, &buf, &count);
818 kunmap_atomic(mapaddr, KM_USER1);
819 } else
820 offset += fuse_copy_do(cs, NULL, &count);
821 }
822 if (page && !cs->write)
823 flush_dcache_page(page);
824 return 0;
825}
826
827/* Copy pages in the request to/from userspace buffer */
828static int fuse_copy_pages(struct fuse_copy_state *cs, unsigned nbytes,
829 int zeroing)
830{
831 unsigned i;
832 struct fuse_req *req = cs->req;
833 unsigned offset = req->page_offset;
834 unsigned count = min(nbytes, (unsigned) PAGE_SIZE - offset);
835
836 for (i = 0; i < req->num_pages && (nbytes || zeroing); i++) {
Miklos Szeredice534fb2010-05-25 15:06:07 +0200837 int err;
838
839 err = fuse_copy_page(cs, &req->pages[i], offset, count,
840 zeroing);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700841 if (err)
842 return err;
843
844 nbytes -= count;
845 count = min(nbytes, (unsigned) PAGE_SIZE);
846 offset = 0;
847 }
848 return 0;
849}
850
851/* Copy a single argument in the request to/from userspace buffer */
852static int fuse_copy_one(struct fuse_copy_state *cs, void *val, unsigned size)
853{
854 while (size) {
Miklos Szeredi1729a162008-11-26 12:03:54 +0100855 if (!cs->len) {
856 int err = fuse_copy_fill(cs);
857 if (err)
858 return err;
859 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700860 fuse_copy_do(cs, &val, &size);
861 }
862 return 0;
863}
864
865/* Copy request arguments to/from userspace buffer */
866static int fuse_copy_args(struct fuse_copy_state *cs, unsigned numargs,
867 unsigned argpages, struct fuse_arg *args,
868 int zeroing)
869{
870 int err = 0;
871 unsigned i;
872
873 for (i = 0; !err && i < numargs; i++) {
874 struct fuse_arg *arg = &args[i];
875 if (i == numargs - 1 && argpages)
876 err = fuse_copy_pages(cs, arg->size, zeroing);
877 else
878 err = fuse_copy_one(cs, arg->value, arg->size);
879 }
880 return err;
881}
882
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700883static int request_pending(struct fuse_conn *fc)
884{
885 return !list_empty(&fc->pending) || !list_empty(&fc->interrupts);
886}
887
Miklos Szeredi334f4852005-09-09 13:10:27 -0700888/* Wait until a request is available on the pending list */
889static void request_wait(struct fuse_conn *fc)
Harvey Harrison5d9ec852008-12-02 14:49:42 +0100890__releases(&fc->lock)
891__acquires(&fc->lock)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700892{
893 DECLARE_WAITQUEUE(wait, current);
894
895 add_wait_queue_exclusive(&fc->waitq, &wait);
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700896 while (fc->connected && !request_pending(fc)) {
Miklos Szeredi334f4852005-09-09 13:10:27 -0700897 set_current_state(TASK_INTERRUPTIBLE);
898 if (signal_pending(current))
899 break;
900
Miklos Szeredid7133112006-04-10 22:54:55 -0700901 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700902 schedule();
Miklos Szeredid7133112006-04-10 22:54:55 -0700903 spin_lock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700904 }
905 set_current_state(TASK_RUNNING);
906 remove_wait_queue(&fc->waitq, &wait);
907}
908
909/*
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700910 * Transfer an interrupt request to userspace
911 *
912 * Unlike other requests this is assembled on demand, without a need
913 * to allocate a separate fuse_req structure.
914 *
915 * Called with fc->lock held, releases it
916 */
Miklos Szeredic3021622010-05-25 15:06:07 +0200917static int fuse_read_interrupt(struct fuse_conn *fc, struct fuse_copy_state *cs,
918 size_t nbytes, struct fuse_req *req)
Harvey Harrison5d9ec852008-12-02 14:49:42 +0100919__releases(&fc->lock)
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700920{
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700921 struct fuse_in_header ih;
922 struct fuse_interrupt_in arg;
923 unsigned reqsize = sizeof(ih) + sizeof(arg);
924 int err;
925
926 list_del_init(&req->intr_entry);
927 req->intr_unique = fuse_get_unique(fc);
928 memset(&ih, 0, sizeof(ih));
929 memset(&arg, 0, sizeof(arg));
930 ih.len = reqsize;
931 ih.opcode = FUSE_INTERRUPT;
932 ih.unique = req->intr_unique;
933 arg.unique = req->in.h.unique;
934
935 spin_unlock(&fc->lock);
Miklos Szeredic3021622010-05-25 15:06:07 +0200936 if (nbytes < reqsize)
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700937 return -EINVAL;
938
Miklos Szeredic3021622010-05-25 15:06:07 +0200939 err = fuse_copy_one(cs, &ih, sizeof(ih));
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700940 if (!err)
Miklos Szeredic3021622010-05-25 15:06:07 +0200941 err = fuse_copy_one(cs, &arg, sizeof(arg));
942 fuse_copy_finish(cs);
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700943
944 return err ? err : reqsize;
945}
946
947/*
Miklos Szeredi334f4852005-09-09 13:10:27 -0700948 * Read a single request into the userspace filesystem's buffer. This
949 * function waits until a request is available, then removes it from
950 * the pending list and copies request data to userspace buffer. If
Miklos Szeredif9a28422006-06-25 05:48:53 -0700951 * no reply is needed (FORGET) or request has been aborted or there
952 * was an error during the copying then it's finished by calling
Miklos Szeredi334f4852005-09-09 13:10:27 -0700953 * request_end(). Otherwise add it to the processing list, and set
954 * the 'sent' flag.
955 */
Miklos Szeredic3021622010-05-25 15:06:07 +0200956static ssize_t fuse_dev_do_read(struct fuse_conn *fc, struct file *file,
957 struct fuse_copy_state *cs, size_t nbytes)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700958{
959 int err;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700960 struct fuse_req *req;
961 struct fuse_in *in;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700962 unsigned reqsize;
963
Miklos Szeredi1d3d7522006-01-06 00:19:40 -0800964 restart:
Miklos Szeredid7133112006-04-10 22:54:55 -0700965 spin_lock(&fc->lock);
Jeff Dikee5ac1d12006-04-10 22:54:53 -0700966 err = -EAGAIN;
967 if ((file->f_flags & O_NONBLOCK) && fc->connected &&
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700968 !request_pending(fc))
Jeff Dikee5ac1d12006-04-10 22:54:53 -0700969 goto err_unlock;
970
Miklos Szeredi334f4852005-09-09 13:10:27 -0700971 request_wait(fc);
972 err = -ENODEV;
Miklos Szeredi9ba7cbb2006-01-16 22:14:34 -0800973 if (!fc->connected)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700974 goto err_unlock;
975 err = -ERESTARTSYS;
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700976 if (!request_pending(fc))
Miklos Szeredi334f4852005-09-09 13:10:27 -0700977 goto err_unlock;
978
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700979 if (!list_empty(&fc->interrupts)) {
980 req = list_entry(fc->interrupts.next, struct fuse_req,
981 intr_entry);
Miklos Szeredic3021622010-05-25 15:06:07 +0200982 return fuse_read_interrupt(fc, cs, nbytes, req);
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700983 }
984
Miklos Szeredi334f4852005-09-09 13:10:27 -0700985 req = list_entry(fc->pending.next, struct fuse_req, list);
Miklos Szeredi83cfd492006-01-16 22:14:31 -0800986 req->state = FUSE_REQ_READING;
Miklos Szeredid77a1d52006-01-16 22:14:31 -0800987 list_move(&req->list, &fc->io);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700988
989 in = &req->in;
Miklos Szeredi1d3d7522006-01-06 00:19:40 -0800990 reqsize = in->h.len;
991 /* If request is too large, reply with an error and restart the read */
Miklos Szeredic3021622010-05-25 15:06:07 +0200992 if (nbytes < reqsize) {
Miklos Szeredi1d3d7522006-01-06 00:19:40 -0800993 req->out.h.error = -EIO;
994 /* SETXATTR is special, since it may contain too large data */
995 if (in->h.opcode == FUSE_SETXATTR)
996 req->out.h.error = -E2BIG;
997 request_end(fc, req);
998 goto restart;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700999 }
Miklos Szeredid7133112006-04-10 22:54:55 -07001000 spin_unlock(&fc->lock);
Miklos Szeredic3021622010-05-25 15:06:07 +02001001 cs->req = req;
1002 err = fuse_copy_one(cs, &in->h, sizeof(in->h));
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001003 if (!err)
Miklos Szeredic3021622010-05-25 15:06:07 +02001004 err = fuse_copy_args(cs, in->numargs, in->argpages,
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001005 (struct fuse_arg *) in->args, 0);
Miklos Szeredic3021622010-05-25 15:06:07 +02001006 fuse_copy_finish(cs);
Miklos Szeredid7133112006-04-10 22:54:55 -07001007 spin_lock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001008 req->locked = 0;
Miklos Szeredic9c9d7d2007-10-16 23:31:05 -07001009 if (req->aborted) {
1010 request_end(fc, req);
1011 return -ENODEV;
1012 }
Miklos Szeredi334f4852005-09-09 13:10:27 -07001013 if (err) {
Miklos Szeredic9c9d7d2007-10-16 23:31:05 -07001014 req->out.h.error = -EIO;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001015 request_end(fc, req);
1016 return err;
1017 }
1018 if (!req->isreply)
1019 request_end(fc, req);
1020 else {
Miklos Szeredi83cfd492006-01-16 22:14:31 -08001021 req->state = FUSE_REQ_SENT;
Miklos Szeredid77a1d52006-01-16 22:14:31 -08001022 list_move_tail(&req->list, &fc->processing);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001023 if (req->interrupted)
1024 queue_interrupt(fc, req);
Miklos Szeredid7133112006-04-10 22:54:55 -07001025 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001026 }
1027 return reqsize;
1028
1029 err_unlock:
Miklos Szeredid7133112006-04-10 22:54:55 -07001030 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001031 return err;
1032}
1033
Miklos Szeredic3021622010-05-25 15:06:07 +02001034static ssize_t fuse_dev_read(struct kiocb *iocb, const struct iovec *iov,
1035 unsigned long nr_segs, loff_t pos)
1036{
1037 struct fuse_copy_state cs;
1038 struct file *file = iocb->ki_filp;
1039 struct fuse_conn *fc = fuse_get_conn(file);
1040 if (!fc)
1041 return -EPERM;
1042
1043 fuse_copy_init(&cs, fc, 1, iov, nr_segs);
1044
1045 return fuse_dev_do_read(fc, file, &cs, iov_length(iov, nr_segs));
1046}
1047
1048static int fuse_dev_pipe_buf_steal(struct pipe_inode_info *pipe,
1049 struct pipe_buffer *buf)
1050{
1051 return 1;
1052}
1053
1054static const struct pipe_buf_operations fuse_dev_pipe_buf_ops = {
1055 .can_merge = 0,
1056 .map = generic_pipe_buf_map,
1057 .unmap = generic_pipe_buf_unmap,
1058 .confirm = generic_pipe_buf_confirm,
1059 .release = generic_pipe_buf_release,
1060 .steal = fuse_dev_pipe_buf_steal,
1061 .get = generic_pipe_buf_get,
1062};
1063
1064static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos,
1065 struct pipe_inode_info *pipe,
1066 size_t len, unsigned int flags)
1067{
1068 int ret;
1069 int page_nr = 0;
1070 int do_wakeup = 0;
1071 struct pipe_buffer *bufs;
1072 struct fuse_copy_state cs;
1073 struct fuse_conn *fc = fuse_get_conn(in);
1074 if (!fc)
1075 return -EPERM;
1076
1077 bufs = kmalloc(pipe->buffers * sizeof (struct pipe_buffer), GFP_KERNEL);
1078 if (!bufs)
1079 return -ENOMEM;
1080
1081 fuse_copy_init(&cs, fc, 1, NULL, 0);
1082 cs.pipebufs = bufs;
1083 cs.pipe = pipe;
1084 ret = fuse_dev_do_read(fc, in, &cs, len);
1085 if (ret < 0)
1086 goto out;
1087
1088 ret = 0;
1089 pipe_lock(pipe);
1090
1091 if (!pipe->readers) {
1092 send_sig(SIGPIPE, current, 0);
1093 if (!ret)
1094 ret = -EPIPE;
1095 goto out_unlock;
1096 }
1097
1098 if (pipe->nrbufs + cs.nr_segs > pipe->buffers) {
1099 ret = -EIO;
1100 goto out_unlock;
1101 }
1102
1103 while (page_nr < cs.nr_segs) {
1104 int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1);
1105 struct pipe_buffer *buf = pipe->bufs + newbuf;
1106
1107 buf->page = bufs[page_nr].page;
1108 buf->offset = bufs[page_nr].offset;
1109 buf->len = bufs[page_nr].len;
1110 buf->ops = &fuse_dev_pipe_buf_ops;
1111
1112 pipe->nrbufs++;
1113 page_nr++;
1114 ret += buf->len;
1115
1116 if (pipe->inode)
1117 do_wakeup = 1;
1118 }
1119
1120out_unlock:
1121 pipe_unlock(pipe);
1122
1123 if (do_wakeup) {
1124 smp_mb();
1125 if (waitqueue_active(&pipe->wait))
1126 wake_up_interruptible(&pipe->wait);
1127 kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
1128 }
1129
1130out:
1131 for (; page_nr < cs.nr_segs; page_nr++)
1132 page_cache_release(bufs[page_nr].page);
1133
1134 kfree(bufs);
1135 return ret;
1136}
1137
Tejun Heo95668a62008-11-26 12:03:55 +01001138static int fuse_notify_poll(struct fuse_conn *fc, unsigned int size,
1139 struct fuse_copy_state *cs)
1140{
1141 struct fuse_notify_poll_wakeup_out outarg;
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001142 int err = -EINVAL;
Tejun Heo95668a62008-11-26 12:03:55 +01001143
1144 if (size != sizeof(outarg))
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001145 goto err;
Tejun Heo95668a62008-11-26 12:03:55 +01001146
1147 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1148 if (err)
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001149 goto err;
Tejun Heo95668a62008-11-26 12:03:55 +01001150
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001151 fuse_copy_finish(cs);
Tejun Heo95668a62008-11-26 12:03:55 +01001152 return fuse_notify_poll_wakeup(fc, &outarg);
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001153
1154err:
1155 fuse_copy_finish(cs);
1156 return err;
Tejun Heo95668a62008-11-26 12:03:55 +01001157}
1158
John Muir3b463ae2009-05-31 11:13:57 -04001159static int fuse_notify_inval_inode(struct fuse_conn *fc, unsigned int size,
1160 struct fuse_copy_state *cs)
1161{
1162 struct fuse_notify_inval_inode_out outarg;
1163 int err = -EINVAL;
1164
1165 if (size != sizeof(outarg))
1166 goto err;
1167
1168 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1169 if (err)
1170 goto err;
1171 fuse_copy_finish(cs);
1172
1173 down_read(&fc->killsb);
1174 err = -ENOENT;
Miklos Szeredib21dda42010-02-05 12:08:31 +01001175 if (fc->sb) {
1176 err = fuse_reverse_inval_inode(fc->sb, outarg.ino,
1177 outarg.off, outarg.len);
1178 }
John Muir3b463ae2009-05-31 11:13:57 -04001179 up_read(&fc->killsb);
1180 return err;
1181
1182err:
1183 fuse_copy_finish(cs);
1184 return err;
1185}
1186
1187static int fuse_notify_inval_entry(struct fuse_conn *fc, unsigned int size,
1188 struct fuse_copy_state *cs)
1189{
1190 struct fuse_notify_inval_entry_out outarg;
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001191 int err = -ENOMEM;
1192 char *buf;
John Muir3b463ae2009-05-31 11:13:57 -04001193 struct qstr name;
1194
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001195 buf = kzalloc(FUSE_NAME_MAX + 1, GFP_KERNEL);
1196 if (!buf)
1197 goto err;
1198
1199 err = -EINVAL;
John Muir3b463ae2009-05-31 11:13:57 -04001200 if (size < sizeof(outarg))
1201 goto err;
1202
1203 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1204 if (err)
1205 goto err;
1206
1207 err = -ENAMETOOLONG;
1208 if (outarg.namelen > FUSE_NAME_MAX)
1209 goto err;
1210
1211 name.name = buf;
1212 name.len = outarg.namelen;
1213 err = fuse_copy_one(cs, buf, outarg.namelen + 1);
1214 if (err)
1215 goto err;
1216 fuse_copy_finish(cs);
1217 buf[outarg.namelen] = 0;
1218 name.hash = full_name_hash(name.name, name.len);
1219
1220 down_read(&fc->killsb);
1221 err = -ENOENT;
Miklos Szeredib21dda42010-02-05 12:08:31 +01001222 if (fc->sb)
1223 err = fuse_reverse_inval_entry(fc->sb, outarg.parent, &name);
John Muir3b463ae2009-05-31 11:13:57 -04001224 up_read(&fc->killsb);
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001225 kfree(buf);
John Muir3b463ae2009-05-31 11:13:57 -04001226 return err;
1227
1228err:
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001229 kfree(buf);
John Muir3b463ae2009-05-31 11:13:57 -04001230 fuse_copy_finish(cs);
1231 return err;
1232}
1233
Tejun Heo85993962008-11-26 12:03:55 +01001234static int fuse_notify(struct fuse_conn *fc, enum fuse_notify_code code,
1235 unsigned int size, struct fuse_copy_state *cs)
1236{
1237 switch (code) {
Tejun Heo95668a62008-11-26 12:03:55 +01001238 case FUSE_NOTIFY_POLL:
1239 return fuse_notify_poll(fc, size, cs);
1240
John Muir3b463ae2009-05-31 11:13:57 -04001241 case FUSE_NOTIFY_INVAL_INODE:
1242 return fuse_notify_inval_inode(fc, size, cs);
1243
1244 case FUSE_NOTIFY_INVAL_ENTRY:
1245 return fuse_notify_inval_entry(fc, size, cs);
1246
Tejun Heo85993962008-11-26 12:03:55 +01001247 default:
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001248 fuse_copy_finish(cs);
Tejun Heo85993962008-11-26 12:03:55 +01001249 return -EINVAL;
1250 }
1251}
1252
Miklos Szeredi334f4852005-09-09 13:10:27 -07001253/* Look up request on processing list by unique ID */
1254static struct fuse_req *request_find(struct fuse_conn *fc, u64 unique)
1255{
1256 struct list_head *entry;
1257
1258 list_for_each(entry, &fc->processing) {
1259 struct fuse_req *req;
1260 req = list_entry(entry, struct fuse_req, list);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001261 if (req->in.h.unique == unique || req->intr_unique == unique)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001262 return req;
1263 }
1264 return NULL;
1265}
1266
1267static int copy_out_args(struct fuse_copy_state *cs, struct fuse_out *out,
1268 unsigned nbytes)
1269{
1270 unsigned reqsize = sizeof(struct fuse_out_header);
1271
1272 if (out->h.error)
1273 return nbytes != reqsize ? -EINVAL : 0;
1274
1275 reqsize += len_args(out->numargs, out->args);
1276
1277 if (reqsize < nbytes || (reqsize > nbytes && !out->argvar))
1278 return -EINVAL;
1279 else if (reqsize > nbytes) {
1280 struct fuse_arg *lastarg = &out->args[out->numargs-1];
1281 unsigned diffsize = reqsize - nbytes;
1282 if (diffsize > lastarg->size)
1283 return -EINVAL;
1284 lastarg->size -= diffsize;
1285 }
1286 return fuse_copy_args(cs, out->numargs, out->argpages, out->args,
1287 out->page_zeroing);
1288}
1289
1290/*
1291 * Write a single reply to a request. First the header is copied from
1292 * the write buffer. The request is then searched on the processing
1293 * list by the unique ID found in the header. If found, then remove
1294 * it from the list and copy the rest of the buffer to the request.
1295 * The request is finished by calling request_end()
1296 */
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001297static ssize_t fuse_dev_do_write(struct fuse_conn *fc,
1298 struct fuse_copy_state *cs, size_t nbytes)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001299{
1300 int err;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001301 struct fuse_req *req;
1302 struct fuse_out_header oh;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001303
Miklos Szeredi334f4852005-09-09 13:10:27 -07001304 if (nbytes < sizeof(struct fuse_out_header))
1305 return -EINVAL;
1306
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001307 err = fuse_copy_one(cs, &oh, sizeof(oh));
Miklos Szeredi334f4852005-09-09 13:10:27 -07001308 if (err)
1309 goto err_finish;
Tejun Heo85993962008-11-26 12:03:55 +01001310
Miklos Szeredi334f4852005-09-09 13:10:27 -07001311 err = -EINVAL;
Tejun Heo85993962008-11-26 12:03:55 +01001312 if (oh.len != nbytes)
1313 goto err_finish;
1314
1315 /*
1316 * Zero oh.unique indicates unsolicited notification message
1317 * and error contains notification code.
1318 */
1319 if (!oh.unique) {
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001320 err = fuse_notify(fc, oh.error, nbytes - sizeof(oh), cs);
Tejun Heo85993962008-11-26 12:03:55 +01001321 return err ? err : nbytes;
1322 }
1323
1324 err = -EINVAL;
1325 if (oh.error <= -1000 || oh.error > 0)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001326 goto err_finish;
1327
Miklos Szeredid7133112006-04-10 22:54:55 -07001328 spin_lock(&fc->lock);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001329 err = -ENOENT;
1330 if (!fc->connected)
1331 goto err_unlock;
1332
Miklos Szeredi334f4852005-09-09 13:10:27 -07001333 req = request_find(fc, oh.unique);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001334 if (!req)
1335 goto err_unlock;
1336
Miklos Szeredif9a28422006-06-25 05:48:53 -07001337 if (req->aborted) {
Miklos Szeredid7133112006-04-10 22:54:55 -07001338 spin_unlock(&fc->lock);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001339 fuse_copy_finish(cs);
Miklos Szeredid7133112006-04-10 22:54:55 -07001340 spin_lock(&fc->lock);
Miklos Szeredi222f1d62006-01-16 22:14:25 -08001341 request_end(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001342 return -ENOENT;
1343 }
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001344 /* Is it an interrupt reply? */
1345 if (req->intr_unique == oh.unique) {
1346 err = -EINVAL;
1347 if (nbytes != sizeof(struct fuse_out_header))
1348 goto err_unlock;
1349
1350 if (oh.error == -ENOSYS)
1351 fc->no_interrupt = 1;
1352 else if (oh.error == -EAGAIN)
1353 queue_interrupt(fc, req);
1354
1355 spin_unlock(&fc->lock);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001356 fuse_copy_finish(cs);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001357 return nbytes;
1358 }
1359
1360 req->state = FUSE_REQ_WRITING;
Miklos Szeredid77a1d52006-01-16 22:14:31 -08001361 list_move(&req->list, &fc->io);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001362 req->out.h = oh;
1363 req->locked = 1;
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001364 cs->req = req;
Miklos Szeredice534fb2010-05-25 15:06:07 +02001365 if (!req->out.page_replace)
1366 cs->move_pages = 0;
Miklos Szeredid7133112006-04-10 22:54:55 -07001367 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001368
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001369 err = copy_out_args(cs, &req->out, nbytes);
1370 fuse_copy_finish(cs);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001371
Miklos Szeredid7133112006-04-10 22:54:55 -07001372 spin_lock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001373 req->locked = 0;
1374 if (!err) {
Miklos Szeredif9a28422006-06-25 05:48:53 -07001375 if (req->aborted)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001376 err = -ENOENT;
Miklos Szeredif9a28422006-06-25 05:48:53 -07001377 } else if (!req->aborted)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001378 req->out.h.error = -EIO;
1379 request_end(fc, req);
1380
1381 return err ? err : nbytes;
1382
1383 err_unlock:
Miklos Szeredid7133112006-04-10 22:54:55 -07001384 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001385 err_finish:
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001386 fuse_copy_finish(cs);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001387 return err;
1388}
1389
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001390static ssize_t fuse_dev_write(struct kiocb *iocb, const struct iovec *iov,
1391 unsigned long nr_segs, loff_t pos)
1392{
1393 struct fuse_copy_state cs;
1394 struct fuse_conn *fc = fuse_get_conn(iocb->ki_filp);
1395 if (!fc)
1396 return -EPERM;
1397
Miklos Szeredic3021622010-05-25 15:06:07 +02001398 fuse_copy_init(&cs, fc, 0, iov, nr_segs);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001399
1400 return fuse_dev_do_write(fc, &cs, iov_length(iov, nr_segs));
1401}
1402
1403static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
1404 struct file *out, loff_t *ppos,
1405 size_t len, unsigned int flags)
1406{
1407 unsigned nbuf;
1408 unsigned idx;
1409 struct pipe_buffer *bufs;
1410 struct fuse_copy_state cs;
1411 struct fuse_conn *fc;
1412 size_t rem;
1413 ssize_t ret;
1414
1415 fc = fuse_get_conn(out);
1416 if (!fc)
1417 return -EPERM;
1418
1419 bufs = kmalloc(pipe->buffers * sizeof (struct pipe_buffer), GFP_KERNEL);
1420 if (!bufs)
1421 return -ENOMEM;
1422
1423 pipe_lock(pipe);
1424 nbuf = 0;
1425 rem = 0;
1426 for (idx = 0; idx < pipe->nrbufs && rem < len; idx++)
1427 rem += pipe->bufs[(pipe->curbuf + idx) & (pipe->buffers - 1)].len;
1428
1429 ret = -EINVAL;
1430 if (rem < len) {
1431 pipe_unlock(pipe);
1432 goto out;
1433 }
1434
1435 rem = len;
1436 while (rem) {
1437 struct pipe_buffer *ibuf;
1438 struct pipe_buffer *obuf;
1439
1440 BUG_ON(nbuf >= pipe->buffers);
1441 BUG_ON(!pipe->nrbufs);
1442 ibuf = &pipe->bufs[pipe->curbuf];
1443 obuf = &bufs[nbuf];
1444
1445 if (rem >= ibuf->len) {
1446 *obuf = *ibuf;
1447 ibuf->ops = NULL;
1448 pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1);
1449 pipe->nrbufs--;
1450 } else {
1451 ibuf->ops->get(pipe, ibuf);
1452 *obuf = *ibuf;
1453 obuf->flags &= ~PIPE_BUF_FLAG_GIFT;
1454 obuf->len = rem;
1455 ibuf->offset += obuf->len;
1456 ibuf->len -= obuf->len;
1457 }
1458 nbuf++;
1459 rem -= obuf->len;
1460 }
1461 pipe_unlock(pipe);
1462
Miklos Szeredic3021622010-05-25 15:06:07 +02001463 fuse_copy_init(&cs, fc, 0, NULL, nbuf);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001464 cs.pipebufs = bufs;
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001465 cs.pipe = pipe;
1466
Miklos Szeredice534fb2010-05-25 15:06:07 +02001467 if (flags & SPLICE_F_MOVE)
1468 cs.move_pages = 1;
1469
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001470 ret = fuse_dev_do_write(fc, &cs, len);
1471
1472 for (idx = 0; idx < nbuf; idx++) {
1473 struct pipe_buffer *buf = &bufs[idx];
1474 buf->ops->release(pipe, buf);
1475 }
1476out:
1477 kfree(bufs);
1478 return ret;
1479}
1480
Miklos Szeredi334f4852005-09-09 13:10:27 -07001481static unsigned fuse_dev_poll(struct file *file, poll_table *wait)
1482{
Miklos Szeredi334f4852005-09-09 13:10:27 -07001483 unsigned mask = POLLOUT | POLLWRNORM;
Miklos Szeredi7025d9a2006-04-10 22:54:50 -07001484 struct fuse_conn *fc = fuse_get_conn(file);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001485 if (!fc)
Miklos Szeredi7025d9a2006-04-10 22:54:50 -07001486 return POLLERR;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001487
1488 poll_wait(file, &fc->waitq, wait);
1489
Miklos Szeredid7133112006-04-10 22:54:55 -07001490 spin_lock(&fc->lock);
Miklos Szeredi7025d9a2006-04-10 22:54:50 -07001491 if (!fc->connected)
1492 mask = POLLERR;
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001493 else if (request_pending(fc))
Miklos Szeredi7025d9a2006-04-10 22:54:50 -07001494 mask |= POLLIN | POLLRDNORM;
Miklos Szeredid7133112006-04-10 22:54:55 -07001495 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001496
1497 return mask;
1498}
1499
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001500/*
1501 * Abort all requests on the given list (pending or processing)
1502 *
Miklos Szeredid7133112006-04-10 22:54:55 -07001503 * This function releases and reacquires fc->lock
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001504 */
Miklos Szeredi334f4852005-09-09 13:10:27 -07001505static void end_requests(struct fuse_conn *fc, struct list_head *head)
Harvey Harrison5d9ec852008-12-02 14:49:42 +01001506__releases(&fc->lock)
1507__acquires(&fc->lock)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001508{
1509 while (!list_empty(head)) {
1510 struct fuse_req *req;
1511 req = list_entry(head->next, struct fuse_req, list);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001512 req->out.h.error = -ECONNABORTED;
1513 request_end(fc, req);
Miklos Szeredid7133112006-04-10 22:54:55 -07001514 spin_lock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001515 }
1516}
1517
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001518/*
1519 * Abort requests under I/O
1520 *
Miklos Szeredif9a28422006-06-25 05:48:53 -07001521 * The requests are set to aborted and finished, and the request
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001522 * waiter is woken up. This will make request_wait_answer() wait
1523 * until the request is unlocked and then return.
Miklos Szeredi64c6d8e2006-01-16 22:14:42 -08001524 *
1525 * If the request is asynchronous, then the end function needs to be
1526 * called after waiting for the request to be unlocked (if it was
1527 * locked).
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001528 */
1529static void end_io_requests(struct fuse_conn *fc)
Harvey Harrison5d9ec852008-12-02 14:49:42 +01001530__releases(&fc->lock)
1531__acquires(&fc->lock)
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001532{
1533 while (!list_empty(&fc->io)) {
Miklos Szeredi64c6d8e2006-01-16 22:14:42 -08001534 struct fuse_req *req =
1535 list_entry(fc->io.next, struct fuse_req, list);
1536 void (*end) (struct fuse_conn *, struct fuse_req *) = req->end;
1537
Miklos Szeredif9a28422006-06-25 05:48:53 -07001538 req->aborted = 1;
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001539 req->out.h.error = -ECONNABORTED;
1540 req->state = FUSE_REQ_FINISHED;
1541 list_del_init(&req->list);
1542 wake_up(&req->waitq);
Miklos Szeredi64c6d8e2006-01-16 22:14:42 -08001543 if (end) {
1544 req->end = NULL;
Miklos Szeredi64c6d8e2006-01-16 22:14:42 -08001545 __fuse_get_request(req);
Miklos Szeredid7133112006-04-10 22:54:55 -07001546 spin_unlock(&fc->lock);
Miklos Szeredi64c6d8e2006-01-16 22:14:42 -08001547 wait_event(req->waitq, !req->locked);
1548 end(fc, req);
Tejun Heoe9bb09d2008-11-26 12:03:54 +01001549 fuse_put_request(fc, req);
Miklos Szeredid7133112006-04-10 22:54:55 -07001550 spin_lock(&fc->lock);
Miklos Szeredi64c6d8e2006-01-16 22:14:42 -08001551 }
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001552 }
1553}
1554
1555/*
1556 * Abort all requests.
1557 *
1558 * Emergency exit in case of a malicious or accidental deadlock, or
1559 * just a hung filesystem.
1560 *
1561 * The same effect is usually achievable through killing the
1562 * filesystem daemon and all users of the filesystem. The exception
1563 * is the combination of an asynchronous request and the tricky
1564 * deadlock (see Documentation/filesystems/fuse.txt).
1565 *
1566 * During the aborting, progression of requests from the pending and
1567 * processing lists onto the io list, and progression of new requests
1568 * onto the pending list is prevented by req->connected being false.
1569 *
1570 * Progression of requests under I/O to the processing list is
Miklos Szeredif9a28422006-06-25 05:48:53 -07001571 * prevented by the req->aborted flag being true for these requests.
1572 * For this reason requests on the io list must be aborted first.
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001573 */
1574void fuse_abort_conn(struct fuse_conn *fc)
1575{
Miklos Szeredid7133112006-04-10 22:54:55 -07001576 spin_lock(&fc->lock);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001577 if (fc->connected) {
1578 fc->connected = 0;
Miklos Szeredi51eb01e2006-06-25 05:48:50 -07001579 fc->blocked = 0;
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001580 end_io_requests(fc);
1581 end_requests(fc, &fc->pending);
1582 end_requests(fc, &fc->processing);
1583 wake_up_all(&fc->waitq);
Miklos Szeredi51eb01e2006-06-25 05:48:50 -07001584 wake_up_all(&fc->blocked_waitq);
Jeff Dike385a17b2006-04-10 22:54:52 -07001585 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001586 }
Miklos Szeredid7133112006-04-10 22:54:55 -07001587 spin_unlock(&fc->lock);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001588}
Tejun Heo08cbf542009-04-14 10:54:53 +09001589EXPORT_SYMBOL_GPL(fuse_abort_conn);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001590
Tejun Heo08cbf542009-04-14 10:54:53 +09001591int fuse_dev_release(struct inode *inode, struct file *file)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001592{
Miklos Szeredi0720b312006-04-10 22:54:55 -07001593 struct fuse_conn *fc = fuse_get_conn(file);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001594 if (fc) {
Miklos Szeredid7133112006-04-10 22:54:55 -07001595 spin_lock(&fc->lock);
Miklos Szeredi1e9a4ed2005-09-09 13:10:31 -07001596 fc->connected = 0;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001597 end_requests(fc, &fc->pending);
1598 end_requests(fc, &fc->processing);
Miklos Szeredid7133112006-04-10 22:54:55 -07001599 spin_unlock(&fc->lock);
Miklos Szeredibafa9652006-06-25 05:48:51 -07001600 fuse_conn_put(fc);
Jeff Dike385a17b2006-04-10 22:54:52 -07001601 }
Miklos Szeredif543f252006-01-16 22:14:35 -08001602
Miklos Szeredi334f4852005-09-09 13:10:27 -07001603 return 0;
1604}
Tejun Heo08cbf542009-04-14 10:54:53 +09001605EXPORT_SYMBOL_GPL(fuse_dev_release);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001606
Jeff Dike385a17b2006-04-10 22:54:52 -07001607static int fuse_dev_fasync(int fd, struct file *file, int on)
1608{
1609 struct fuse_conn *fc = fuse_get_conn(file);
1610 if (!fc)
Miklos Szeredia87046d2006-04-10 22:54:56 -07001611 return -EPERM;
Jeff Dike385a17b2006-04-10 22:54:52 -07001612
1613 /* No locking - fasync_helper does its own locking */
1614 return fasync_helper(fd, file, on, &fc->fasync);
1615}
1616
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -08001617const struct file_operations fuse_dev_operations = {
Miklos Szeredi334f4852005-09-09 13:10:27 -07001618 .owner = THIS_MODULE,
1619 .llseek = no_llseek,
Badari Pulavartyee0b3e62006-09-30 23:28:47 -07001620 .read = do_sync_read,
1621 .aio_read = fuse_dev_read,
Miklos Szeredic3021622010-05-25 15:06:07 +02001622 .splice_read = fuse_dev_splice_read,
Badari Pulavartyee0b3e62006-09-30 23:28:47 -07001623 .write = do_sync_write,
1624 .aio_write = fuse_dev_write,
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001625 .splice_write = fuse_dev_splice_write,
Miklos Szeredi334f4852005-09-09 13:10:27 -07001626 .poll = fuse_dev_poll,
1627 .release = fuse_dev_release,
Jeff Dike385a17b2006-04-10 22:54:52 -07001628 .fasync = fuse_dev_fasync,
Miklos Szeredi334f4852005-09-09 13:10:27 -07001629};
Tejun Heo08cbf542009-04-14 10:54:53 +09001630EXPORT_SYMBOL_GPL(fuse_dev_operations);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001631
1632static struct miscdevice fuse_miscdevice = {
1633 .minor = FUSE_MINOR,
1634 .name = "fuse",
1635 .fops = &fuse_dev_operations,
1636};
1637
1638int __init fuse_dev_init(void)
1639{
1640 int err = -ENOMEM;
1641 fuse_req_cachep = kmem_cache_create("fuse_request",
1642 sizeof(struct fuse_req),
Paul Mundt20c2df82007-07-20 10:11:58 +09001643 0, 0, NULL);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001644 if (!fuse_req_cachep)
1645 goto out;
1646
1647 err = misc_register(&fuse_miscdevice);
1648 if (err)
1649 goto out_cache_clean;
1650
1651 return 0;
1652
1653 out_cache_clean:
1654 kmem_cache_destroy(fuse_req_cachep);
1655 out:
1656 return err;
1657}
1658
1659void fuse_dev_cleanup(void)
1660{
1661 misc_deregister(&fuse_miscdevice);
1662 kmem_cache_destroy(fuse_req_cachep);
1663}